<!DOCTYPE html>
<html>
<head>
    <meta charset="UTF-8">
    <title>数独分享封面</title>
    <style>
        /* 基础样式重置 */
        * {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }

        /* 容器样式 */
        .share-cover {
            width: 500px;
            height: 400px;
            background: linear-gradient(135deg, #F8FAFC 0%, #E3F2FD 100%);
            display: flex;
            flex-direction: column;
            align-items: center;
            justify-content: center;
            padding: 20px;
            font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
        }

        /* 数独棋盘样式 */
        .sudoku-board {
            width: 180px;
            height: 180px;
            background: white;
            border-radius: 8px;
            box-shadow: 0 4px 12px rgba(0,0,0,0.1);
            display: grid;
            grid-template-columns: repeat(3, 1fr);
            gap: 2px;
            padding: 2px;
            margin-bottom: 4px;
            position: relative;
        }

        .sudoku-cell {
            background: white;
            border: 1px solid #E0E0E0;
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 24px;
            color: #2C3E50;
            font-weight: 500;
        }

        /* 铅笔图标 */
        .pencil {
            position: absolute;
            right: -40px;
            top: 50%;
            transform: translateY(-50%);
            font-size: 32px;
            color: #F5A623;
        }

        /* 文字样式 */
        .title {
            font-size: 28px;
            color: #2C3E50;
            font-weight: bold;
            margin-bottom: 0px;
        }

        .subtitle {
            font-size: 16px;
            color: #4A90E2;
            opacity: 0.8;
        }

        /* 装饰元素 */
        .floating-numbers {
            position: absolute;
            font-size: 14px;
            color: #4A90E2;
            opacity: 0.2;
        }

        .n1 { top: 10%; left: 10%; }
        .n2 { top: 20%; right: 15%; }
        .n3 { bottom: 15%; left: 20%; }
    </style>
</head>
<body>
    <div class="share-cover">
        <!-- 装饰性数字 -->
        <div class="floating-numbers n1">3</div>
        <div class="floating-numbers n2">7</div>
        <div class="floating-numbers n3">4</div>

        <!-- 数独棋盘 -->
        <div class="sudoku-board">
            <div class="sudoku-cell">7</div>
            <div class="sudoku-cell">1</div>
            <div class="sudoku-cell"></div>
            <div class="sudoku-cell"></div>
            <div class="sudoku-cell">4</div>
            <div class="sudoku-cell">2</div>
            <div class="sudoku-cell">5</div>
            <div class="sudoku-cell"></div>
            <div class="sudoku-cell">9</div>
            
            <!-- 铅笔图标 -->
            <div class="pencil">✏️</div>
        </div>

        <!-- 文字部分 -->
        <h1 class="title">数独挑战</h1>
        <p class="subtitle">提升思维 · 享受乐趣</p>
    </div>
</body>
</html>